Goal 1: Increase gantry rigidity.
After trying the dual 20x60 gantry like the OX, I was still not happy with how much flex I was getting. This was most noticeable when plunging and drilling. So I have added 3 things to improve this.

Quad 20x60 extrusions.

Face bolting the extrusions together. (Tig welding would be better)

Increased side plates to 8 inches (200mm)

Goal 2: Use my existing timing belt drive
I already build a 1500x1500 CNC using the belt and pinion system, so I would like to test Goal 1 without needing to purchase all new motors and lead screws. Therefore I added motor mounts for NEMA 17 and NEMA 23 belt and pinion.

Goal 3: Allow for Acme Lead Screw upgrade
To further increase performance and accuracy I plan to upgrade both X and Y to 1/2 inch ACME Lead screws. Here are a few links for what you need: